The present invention relates generally to communications, and more particularly to network communications over the present telecommunications infrastructure and emerging self-contained networks using public telephone switching systems, Internet and telephony protocol networks, special service networks, and high capacity networks.
Currently virtual private network (VPN) is a very popular method for achieving private network connectivity between distributed locations by using public networks, like the Internet, frame relay networks, etc. In VPN, different schemes are implemented to limit the routing of the network packets to destination nodes that are part of the VPN, thereby creating the effect of having a dedicated private network. The use of public packet networks was a natural choice for this, as the cost of deploying packet technology was lower than building dedicated network connections.
Recent developments in fiber optics have resulted in a new reality, however, in which there is excess bandwidth available on backbone network segments with the use of dense wavelength division multiplexing (DWDM). Using this ample availability of bandwidth another method for building private networks can be implemented, one which the present inventor terms xe2x80x9cdynamic private networkxe2x80x9d (DPN). A key principle in DPN is to use well known circuit switching techniques, as used in telephone networks, and to apply these to provide on-demand connections for carrying packet traffic. The present inventor""s prior invention, a bandwidth transfer switching system (BTSS), provides one logical framework for implementing DPN.
FIG. 1 (background art) is a block diagram depicting the existing communications infrastructure 10. Various devices may communicate via this infrastructure 10, and users today often have and use multiple such devices, like telephones 12a, facsimiles 12b, modems 12c, computers 12d, special service devices 12e, and local area networks (LAN 12f)(representing collections of computers and other network enabled equipment behind a router or switch). Examples of these are shown here connected to a public switched telephone network (PSTN 14). The telephones 12a and facsimiles 12b are analog devices which may communicate with respective like devices. The modems 12c stylistically depict the still common situation of digital devices producing digital signals that are converted to, from, and generally communicated as analog type signals. In contrast, the computers 12d, special service devices 12e, and LAN 12f here are true digital devices.
While the presence of computers 12d and LAN 12f in the existing infrastructure 10 is relatively well known, the use of special service devices 12e may be less widely appreciated. These are, however, increasingly common today. Some examples include remote monitorable utility meters and alarm systems. Such special service devices 12e typically require a much lower data transfer rate than systems like the computers 12d and LAN 12f. 
For communications between the respective sets of like devices, the analog xe2x80x9ctrafficxe2x80x9d may travel entirely via the PSTN 14. In contrast, the digital traffic for the computers 12d and particularly the LAN 12f may start on the PSTN 14 and then proceed via an Internet protocol network (IP network 16). Similarly, the digital traffic for the special service device 12e may start on the PSTN 14 and then proceed via a signal switching network, like the signaling system 7 network (SS7 network 18) shown.
FIG. 2 (background art) is a block diagram depicting a more suitable network evolution model. A broadband network 22 and a generalized high capacity network 24 are added here, and video units 12g are an added device type. The various communications devices 12a-g here connect to an access network 20, and the access network 20 connects to the PSTN 14 (essentially the major central element already in the existing infrastructure 10). The access network 20 also connects to the IP network 16, the SS7 network 18, a broadband network 22, and the high capacity network 24. These collectively form a network matrix 26 in which the PSTN 14 handles analog traffic, the IP network 16 and the SS7 network 18 can handle most digital communications, and the broadband network 22 handles specialized high-bandwidth communications such as digital video.
The high capacity network 24 handles emerging very high-bandwidth digital communications. This is increasingly used as part of a communications xe2x80x9cbackbone,xe2x80x9d typically implemented in SONET/SDH/DSx. The high capacity network 24 is often implemented using fiber optics. But this is not necessarily the case. For example, satellite links are also used.
For this discussion, the scheme depicted in FIG. 2 can be termed a bandwidth transfer switching system (BTSS 28). The BTSS 28 is according to a previous invention by the present inventor, and is detailed in International App. No PCT/US00/01039 and U.S. pat. app. Ser. No. 09/622,252, hereby incorporated by reference in their entirety. The BTSS 28 provides an efficient and logical framework for implementing the present invention, but other conventional communications networks may also be used.
FIG. 3 (background art) is a block diagram showing an access network 20 and the linkages therein. Specifically, the access network 20 here is one as would be used in the BTSS 28. Of course, FIG. 3 depicts only one xe2x80x9cendxe2x80x9d of the BTSS 28, and at least one other instance of the access network 20 (or suitable equivalent) would be connected via the PSTN 14, the IP network 16, etc.
The access network 20 includes or is connected to customer premises equipment (CPE 30). The telephones 12a, facsimiles 12b, modems 12c, computers 12d, special service devices 12e, and LAN 12f of FIG. 1 are common examples of CPE 30. The access network 20 further includes an access concentrator 32, a remote concentrator 34, a transfer switch 36, and a central office switch 38. As covered in detail in the disclosures of BTSS, the access concentrator 32 and remote concentrator 34 are new under BTSS and the transfer switch 36 and central office switch 38 are essentially conventional. Furthermore, in some embodiments the remote concentrator 34 can be dispensed with, and the access concentrators 32 able to directly work with the transfer switches 36. This will be treated as the case throughout the rest of this discussion.
FIG. 1-3 summarize the existing communications infrastructure 10 and the BTSS 28 extension of it. Within this we find the current situation. Existing data protocols, like TCP/IP, are built for addressing the needs of connecting larger numbers of computers on a peer-to-peer basis (from a network point of view). However, with the widespread deployment and use of computing devices, there are actually three broad types of networking needs. First, there is the need to interconnect and inter operate with distributed network devices (with each network device viewed as a standalone entity from a network perspective). Second, there is the need for a remote device to connect to a group of network devices that form a functional group, i.e., logical networks (a group of network devices that provide a collection of applications and services, e.g., a corporate local area network (LAN)). This situation can be considered to be a special case of the following third case. Third, there is the need for distant logical networks (corporate LANs) to be seamlessly integrated to form a single logical unit (a distributed logical network), even though such may be geographically distributed.
Current Internet protocols were primarily developed to address the first need enumerated above, and this has left the second and third needs much wanting. Accordingly, what is needed is a combination of the best of both packet switching and circuit switching to leverage the existing communication infrastructure and technologies to produce superior functionality.
Accordingly, it is an object of the present invention to provide a dynamic private network (DPN) having superior network system performance and reduced system complexity.
Another object of the invention is to provide a framework for incrementally enhancing current network infrastructure for future network needs.
And another object of the invention is to provide network capabilities that are current not possible or feasible.
Briefly, one preferred embodiment of the present invention is a dynamic private network (DPN) for communicating between customer premises equipment (CPE). The DPN includes access concentrators each connecting to instances of the CPE to form logical networks. Dynamic private network routers (DPN routers) each connect to at least one such logical network. A datapath network connects the DPN routers, permitting communications between the CPE in the respective logical networks. And a status and control network (SOC network) connects to the datapath network to permit controlling operation of the DPN.
An advantage of the present invention is that it does provide superior network system performance and reduced system complexity.
Another advantage of the invention is that it does provide for incremental enhancement, both of the current network infrastructure and to permit rapid and efficient future network growth. The invention particularly enhances the functionality of existing network infrastructures without wholesale element replacement. Concurrently, the invention reduces the cost of building networks by decreasing the cost of network nodes, particularly due to decreased complexity.
And another advantage of the invention is that it does provide capabilities that are not otherwise possible or feasible, particularly with respect to network control and security. With regard to network security, the invention particularly permits efficiently handling growing threats such as denial of service (DoS) and distributed DoS (DDoS) attacks.
These and other objects and advantages of the present invention will become clear to those skilled in the art in view of the description of the best presently known mode of carrying out the invention and the industrial applicability of the preferred embodiment as described herein and as illustrated in the several figures of the drawings.